"Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths
This is the final version of the article. Available from Geological Society via the DOI in this record. It is widely held that benthic foraminifera exhibit species-specific calcification depth preferences, with their tests recording sediment pore water chemistry at that depth (i.e. stable isotope an...
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ftunivexeter:oai:ore.exeter.ac.uk:10871/31481 2024-09-15T17:45:27+00:00 "Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths Dejardin, R Kender, S Allen, CS Leng, MJ Swann, GEA Peck, VL 2018 http://hdl.handle.net/10871/31481 https://doi.org/10.5194/jm-37-25-2018 en eng Geological Society Vol. 37, pp. 25 - 71 doi:10.5194/jm-37-25-2018 http://hdl.handle.net/10871/31481 0262-821X Journal of Micropalaeontology © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Article 2018 ftunivexeter https://doi.org/10.5194/jm-37-25-2018 2024-07-29T03:24:16Z This is the final version of the article. Available from Geological Society via the DOI in this record. It is widely held that benthic foraminifera exhibit species-specific calcification depth preferences, with their tests recording sediment pore water chemistry at that depth (i.e. stable isotope and trace metal compositions). This assumed depth-habitat-specific pore water chemistry relationship has been used to reconstruct various palaeoenvironmental parameters, such as bottom water oxygenation. However, many deepwater foraminiferal studies show wide intra-species variation in sediment living depth but relatively narrow intra-species variation in stable isotope composition. To investigate this depth-habitat-stable-isotope relationship on the shelf, we analysed depth distribution and stable isotopes of "living" (Rose Bengal stained) benthic foraminifera from two box cores collected on the South Georgia shelf (ranging from 250 to 300m water depth). We provide a comprehensive taxonomic analysis of the benthic fauna, comprising 79 taxonomic groupings. The fauna shows close affinities with shelf assemblages from around Antarctica. We find "live" specimens of a number of calcareous species from a range of depths in the sediment column. Stable isotope ratios (δ 13 C and δ 18 O) were measured on stained specimens of three species, Astrononion echolsi, Cassidulinoides porrectus, and Buccella sp. 1, at 1 cm depth intervals within the downcore sediment sequences. In agreement with studies in deep-water settings, we find no significant intra-species variability in either δ 13 C foram or δ 18 O foram with sediment living depth on the South Georgia shelf. Our findings add to the growing evidence that infaunal benthic foraminiferal species calcify at a fixed depth. Given the wide range of depths at which we find "living", "infaunal" species, we speculate that they may actually calcify predominantly at the sediment-seawater interface, where carbonate ion concentration and organic carbon availability is at a maximum. This ... Article in Journal/Newspaper Antarc* Antarctica Southern Ocean University of Exeter: Open Research Exeter (ORE) Journal of Micropalaeontology 37 1 25 71 |
institution |
Open Polar |
collection |
University of Exeter: Open Research Exeter (ORE) |
op_collection_id |
ftunivexeter |
language |
English |
description |
This is the final version of the article. Available from Geological Society via the DOI in this record. It is widely held that benthic foraminifera exhibit species-specific calcification depth preferences, with their tests recording sediment pore water chemistry at that depth (i.e. stable isotope and trace metal compositions). This assumed depth-habitat-specific pore water chemistry relationship has been used to reconstruct various palaeoenvironmental parameters, such as bottom water oxygenation. However, many deepwater foraminiferal studies show wide intra-species variation in sediment living depth but relatively narrow intra-species variation in stable isotope composition. To investigate this depth-habitat-stable-isotope relationship on the shelf, we analysed depth distribution and stable isotopes of "living" (Rose Bengal stained) benthic foraminifera from two box cores collected on the South Georgia shelf (ranging from 250 to 300m water depth). We provide a comprehensive taxonomic analysis of the benthic fauna, comprising 79 taxonomic groupings. The fauna shows close affinities with shelf assemblages from around Antarctica. We find "live" specimens of a number of calcareous species from a range of depths in the sediment column. Stable isotope ratios (δ 13 C and δ 18 O) were measured on stained specimens of three species, Astrononion echolsi, Cassidulinoides porrectus, and Buccella sp. 1, at 1 cm depth intervals within the downcore sediment sequences. In agreement with studies in deep-water settings, we find no significant intra-species variability in either δ 13 C foram or δ 18 O foram with sediment living depth on the South Georgia shelf. Our findings add to the growing evidence that infaunal benthic foraminiferal species calcify at a fixed depth. Given the wide range of depths at which we find "living", "infaunal" species, we speculate that they may actually calcify predominantly at the sediment-seawater interface, where carbonate ion concentration and organic carbon availability is at a maximum. This ... |
format |
Article in Journal/Newspaper |
author |
Dejardin, R Kender, S Allen, CS Leng, MJ Swann, GEA Peck, VL |
spellingShingle |
Dejardin, R Kender, S Allen, CS Leng, MJ Swann, GEA Peck, VL "Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths |
author_facet |
Dejardin, R Kender, S Allen, CS Leng, MJ Swann, GEA Peck, VL |
author_sort |
Dejardin, R |
title |
"Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths |
title_short |
"Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths |
title_full |
"Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths |
title_fullStr |
"Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths |
title_full_unstemmed |
"Live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore South Georgia, Southern Ocean: Implications for calcification depths |
title_sort |
"live" (stained) benthic foraminiferal living depths, stable isotopes, and taxonomy offshore south georgia, southern ocean: implications for calcification depths |
publisher |
Geological Society |
publishDate |
2018 |
url |
http://hdl.handle.net/10871/31481 https://doi.org/10.5194/jm-37-25-2018 |
genre |
Antarc* Antarctica Southern Ocean |
genre_facet |
Antarc* Antarctica Southern Ocean |
op_relation |
Vol. 37, pp. 25 - 71 doi:10.5194/jm-37-25-2018 http://hdl.handle.net/10871/31481 0262-821X Journal of Micropalaeontology |
op_rights |
© Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. |
op_doi |
https://doi.org/10.5194/jm-37-25-2018 |
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Journal of Micropalaeontology |
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37 |
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1 |
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25 |
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71 |
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1810493281121861632 |